High separation performance of carbon dioxide-based poly(ether-carbonate) copolymer for gas chromatographic analyses

This work presents the investigation of a novel CO₂-based poly(ether-carbonate) copolymer, namely poly(propylene ether-carbonate)diol (PPCD), for gas chromatographic (GC) analyses. The PPCD column exhibited column efficiency of 4000 plates/m determined by naphthalene at 120 ℃ with the retention factor 6.23. Its separation performance was investigated by adopting a wide variety of analytes and isomers, including the isomer mixtures of alkanes, substituted benzene isomers with diverse groups, phenols and anilines, and the mixtures of organic solvents of high volatility, aliphatic amines and N-heterocycles. As a result, the PPCD column displayed distinctly higher resolving capability than the commercial columns described herein and achieved high column inertness towards acidic/basic analytes without involving any deactivation procedure. Additionally, it displayed excellent separation repeatability and reproducibility with the relative standard deviation (RSD) values less than 0.01% for within-day and in the range of 0.26% - 0.36% for between-day and 3.0% - 4.1% for between-column (n = 4). Further, the PPCD column (30 m) was used to GC-MS analysis of the lemongrass essential oil and resolved more components well than the indicated commercial columns, evidencing its outstanding separation performance for analyses of complex samples. Up to date, the CO₂-based poly(ether-carbonate) copolymers are not reported in the field of chromatography. This work demonstrates their promising future as a new type of selective and inert stationary phases for practical GC analyses.